Method of making engine-cylinders.



M. FISCHER. METHOD OF MAKING ENGINE OYLINDERS.

APPLIQATION FILED APR. 29, 1914.

Patented Oct. 13, 1914.

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UNITED STATES. PATENT OFF R 1 MARTIN FISCHER, or ZURICH, SWITZERLAND, Assrenon'ro eats oron CORPORATION, A CORPORATION on NEW YORK.

METHOD or MAKING ENGINE-CYLINDERS.

Specification of Letters Patent. Pgitented Qct; 1914.

Original application filed January 12, 1912, Serial No. 670,904. Divided and. this application filed April 29,

. 1914. Serial No. 835,103. I

To all whom it may concern: I

Be it known that I, MARTIN FIsGHER, a,

670,904, entitled Combustion-engine of which I this is a divisional application. 1

This application relates to method or rocess of manufacturing a structure embodying the invention fully set forth in said original application, as will hereinafter apear. p In the drawings Figure 1 is a vertical section of a cylinder showing valves and recesses with piston in position; Fig. 2 is a transverse section of the cylinder; Fig. 3 is a diagram to illustrate the method of manufacture of cylinder and valves embodying the particular features shown in Figs. 1 and 2.

In the drawings lis a cylinder having at 1 an integral head; 2-2 are valves engaging piston 33, and set in recesses 4-4:. Each of the valves 2 is a slide valve of crescent form in cross section, each adapted to reciprocate in a recess 4, which is corres 0ndingly crescent shaped in section, that is the space between the surface of the piston and the outer side or back of the recess constitutes a crescent shaped space.

Through the sides of the cylinder wall are ports connecting with the recesses and alternately closed and opened by the reciprocation of the slide valves according to the desired cycle of the engine.

In the form of slide valve and recess shown it will be particularly noted that the circular section of all the working faces se cure an easy working and a safe packing of the surfaces. I 1

Parts of my method of construction may be applicable with changes in some of the features of construction; but in the particular form shown the construction may be effected as follows: both bores, forming the guide face of the slide valves, are made first in the solid cylinder the slide valves, shaped out; of a solid; turned and lengthwise cut cylinder, are then placed in the bores and screwed tight from the outside; after this the cylinder is bored. This I method may be applicable in small cylinders individually made, but is not intendedfor-quantity production.

In motors where the cylinders are always castwith ahollow center for'the bore, the construction may be carried out as follows:

y The working surfaces ofthe slide valves, as atl F g. 3 are first bored or turned and may be finished on a circular grinder. The slide valves, still rough on the side intended to engage the piston, but finished on the backs or outside, are then put into placeand screened fast by lag screws or. any suitable method from the outside. Then the inner face of the cylinder is bored through, finishing the inner surface of the cylinder proper as well as the inner surface of the valve or valves. It will be seen that by this method both faces of the slide valves as well as the cylinder can be produced by turning, boring or circular grinding, in a manner greatly facilitating production.

In the first of the two methods above described the valve seat is bored with a tool cutting throughout the circumference of the bore as the solid material in the center of what afterward becomes the cylinder bore,

insures-the even cutting of the boring tool. lVhile boring the cylinder with thevalve pieces secured in theirseats, the boring cut of the cylinder proper is also continuously in the material and insures a uniform cut. It has been found that when carefully done there is no tearing 0r chipping of the metal where the material above the valve joins the cylinder surface. This may be particularly. distinguished if we consider an attempt to produce this construction of cylinder by first boring the cylinder throughout and thencutting the recesses in the sides with an arbor supported at either end. In this way thetoolwould cut the recess only during a part of its revolution, being a one sided out which would tend to spring the arbor and prevent accuracy. Such inaccuracy would be accentuated when boring the cylinder with integral head, as shown in the drawings, resulting in great difliculty if not the impossibility of machining sufficiently close to dimensions to make the valve operation possible without prohibitive expense.

While I have illustratedand described one form of practising my method it is possible to modify it in some respects without departing from my invention, but

What I claim and desire to secure by Let ters Patent is:

1. A process for the construction of a motor of the character described consisting in boring the slide valve tracks, placing slide valves, out: out of a solid cylinder in said bores, thereupon boring the cylinder proper, whereby all working surfaces are produced by turning, boring or circular grinding.

2., A method for the construction of motors'consisting of boring a recess longitud'n nally in the side ofthe cylinder, inserting therein a slide valve, and finish-boring or grinding of the internal surface of the cylinder with the valve. in position. 1

3. A method of machining engine cylinders consisting of'forming'in a hollow cylinder casting a longitudinal depression in the side to constitute a valve seat, forming the outside or back of a sllding valve to conform to said seat and securing it in the seat, and thereupon finish-boring the cylinder and interior face of the valve at the same time.

' 4. A method of constructing an engine cylinder and valve seat consisting of effect-- ing a sectional cylindrical out from the inside into the inner wall of the cylinder, and thereafter finishing the main inner surface of the cylinder.

5. A method of machining the interior of an engine cylinder with valve seat consisting of cutting on a cylindrical section the :material away from the side of the proposed iinterior cylindrical surface on a radius less than the radius of the cylinder boring, fitting and securing a valve in said cylindrical jsectional recess, and thereafter finishing the interior wall of the cylinder and the valve at the same time.

In testimony whereof I have signed my :name to this specification, in the presence of two subscribing witnesses, this 3rd day of April, 1914.

MARTIN FISCHER.

Witnesses CARL GRnLsEN, FRANK Bonn.

Copies of this patent may be obtained for five centsieach, by addressing the Commissioner of Patents, Washington, D. G. 

